I have never seen anyone posting about them and, in fact, I don't think mozzarella sticks are on any of the WDW menus.
If you follow the link in my signature to the disABILITIES FAQs thread, post #3 has some resources that might be helpful. There are links to the menus from wdwinfo.com and allearsnet.com
There is also contact information for WDW dietary department, which may be able to help with your question.